Mock apple pie looks and tastes like apple pie, but it contains no apples. The filling is made from crackers. The best-known recipe uses Ritz crackers, which Nabisco introduced in 1934.
The usual story is that the recipe was invented during the Great Depression. It is older. Newspapers printed apple-free apple pie recipes in 1857, and soda crackers were called for by 1869. The pie was “popular among pioneer families crossing the Great Plains.” One food writer calls the Depression story “untrue,” spread “probably by the Nabisco marketing folks.”